Safety cranking device for internal-combustion engines.



F. DION. SAFETY CRANKING DEVICE FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED MAR. 29, 1911.

1,049,061 Patented Dec. 31, 1912.

UNITED STATES PATENT OFFICE.

FRANCOIS DION, OF MANCHESTER, NEW HAMPSHIRE.

SAFETY CRANKING DEVICE FOR INTERNAL-COMBUSTION ENGINES.

To all whom it may concern:

Be it known that I, FRANCOIS DION, a subject of the King of Great Britain, residing at'Manohester, county of Hillsboro, and State of New Hampshire, have invented an Improvement in Safety Cranking Devices for Internal-CombustionEngines, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to cranking devices for internal combustion engines of that type which are provided with means for automatically disengaging the starting crank from the engine shaft upon the occurrence of a back kick.

' which is The object of the invention is to provide a simple mechanism of this nature which can be inexpensively manufactured and which will be effective in operation.

I will first describe one embodiment of the invention and will then point out the novel features in the appended claims.

Referring to the drawings Figure 1 is a sectional view of a cranking device embodying my invention, said section being taken on substantially the line ac -w, Fig. 2; Fig. 2 is a top lan view of Fig. 1; Fig. 3 is a section on t e line yy, Fig. 1; Fig. 4 is a section on the line a-a Fig. 1.

1 designates a shaft leading to the engine and which may be the crank shaft or any other shaft by which the engine is started. For convenience I will hereinafter refer to said shaft 1 as the engine shaft.

2 designates the starting crank shaft rovided with a crank handle 3 by which it may be turned. This starting crank shaft is mounted in a suitable bearing 4 to have both longitudinal and rotary movement therein.

5 designates part of the engine frame or any other suitable sup ort in which the end of the engine shaft 1 1S journaled.

The engine shaft 1 is provided with a shaft extension 6 which is herein shown as a stud screw-threaded into the end of the engine shaft as at 7. This shaft extension has rigid therewith a clutch member 8 which 18 provided with the usual clutch teeth 9 that are adapted to be engaged by cooperating clutch teeth 10 associated with the starting crank shaft for turning the. engine shaft forward. The starting crank shaft 2 has associated therewith a shaft ex- Specification of Letters Patent.

Application filed March 29, 1911.

Patented Dec. 31,1912.

Serial No. 617,552.

tension 12 in the form of a sleeve which telescopes over the shaft extension 6 and which is provided with the clutch teeth 10. This extension 12 is preferably made separate from the shaft 2, although it might be integral therewith if desired. I prefer to make it separate in order to facilitate the assembling of the parts, and as herein shown, the shaft 2 is rovided with the recessed head 11 into w ich the reduced end 13 of the extension 12 is screw-threaded and the shaft extension 6 is shown as having a nut 14 thereon which is received in the recess in the head 11 and which by its engagement with the extension 12 prevents the parts from being separated.

Loosely surroundin the extension 12 is a ratchet member 15 which is held from movement longitudinally of the shaft and which can freely rotate in onedirection but is prevented from rotating in a backward direction. Said ratchet member 15 is held from longitudinal movement by being confined in an annular recess 16 formed in a casing 17 that incloses the clutch members, and this casing 17 has pivoted therein'the spring- -pressed pawls 18 which prevent backward rotation of the ratchet member, while permitting it to rotate forwardly. This casing 17 may be supported in any suitable way, but is herein shown as formed with a flange 19 which is bolted or otherwise secured to the frame 5. The casing 17 may conveniently be made in two parts which are bolted or clamped together by bolts 20.-

The ratchet member 17 has integral therewith teeth 21 having inclined faces and the sleeve 12 has rigid therewith a clutch-disengaging member 22 provided with teeth 23 having inclined faces that are adapted to engage the teeth 21. A spring 24 encircling the starting crank shaft 2 normally tends to hold the clutch-disengaged as shown in Fig. 1.

In order to start the engine the starting crank shaft 2 is moved longitudinally so as to bring the clutch teeth9 and 10 into engagement in usual manner, and this longitudinal movement also brings the clutch teeth 21 and 23 into engagement, as seen in Fig. 2. \Vhen the clutch teeth are thus engaged a turning movement of the crank handle in the proper direction will turn the shaft 2 in the direction of the arrow a, Fig. 3, thus turning the engine shaft 1 forwardly to start the engine, and during this h the teeth 1 member 15 ask kick occurs, rotate backwardly,

- ard movement to however, is held the pawls 18 and t does rotate a of the teeth tunnel movement of 'ch is sufiicient ii 2; and 10 therel. to continue its out carrying with win s have been "ng of the in engine shaft l d faces associated inv mien, however, the clutch inci'nbers .5 and the ratchet mem iii and the e xh- Jnnecting mem- 22 nae-d mthin the casing 1.? and are, ore, kept entirely clean and free from dirt. 'ifiioremer, the device is extremely compact and takes up no more room than the {n."dinar cranking device. It can, than? be appiied to any engine change in the construce e; 1 be readily taken apart by nn g inc mad 11 from the part l2 and then r 'n the nut 14.

Having fully d V w my invention, it I ciaim as new an desire to secure by Letters Patent ist---- The can an engine shaft having an e: mi having rigid therewith clutch teeth, of a iongitndinall -movable starting crank shafthaving a etachable extensir'm w ieh telescopes over the engine shaft ex? n and. is provided with cintch teeth to tl' c on the engine shaft extension detachsoh: extension from being removed, a ratchet member loosely mounted s d achabie extension, nvans to ard retation of the ratchet nn Latter having inclined ratchet member teeth thereon extending laterally therefrom and coiiperating teeth on the starting crank shaft extension to engage the inclined teeth on the ratchet member when the clutch members are in ngagement.

-2. The combination with an engine shaft having a shaft extension and having rigid therewith clutch teeth, of a longitudinallymovable starting crank shaft having a detachable extension which telescopes over the engine shaft extension and is provided with clutch teeth to engage those on the engine shaft, means on. the engine shaft extension to prevent the detachable extension from being withdrawn from the ergine shaft ex tension, which means are accessible when the starting shaft is disconnected from its extension, a ratchet member loosely mounted on the starting crank shaft extension and provided with laterally-extending inclined teeth, meansto prevent backward rotation of the ratchet member, and inclined teeth on said detachable extension to, engage those on the ratchet member when the clutch members are in en agement.

through which the shaft extendsila casing secured to the fixed member and aving an interior annular groove, a collar on the engine shaft situated within the casing and provided with clutch teeth, a starting crank shaft having an extension which telescopes over the engine shaft extension and is provided with clutch teeth to engage those on the engine shaft, a ratchet member loosely mounted on the starting crank shaft extension and occupying and held in position by said groove, means carried by said casing to prevent backward rotation of said ratchet member, inclined teeth extendinglatprally from. the ratchet member, and 00- operating inclined teeth extending laterally from the starting crank shaft extension.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

- FRANCOIS DION.

Witnesses:

F. A. PREVOST, MAUI) I. Dronzm.

' Gents: at this natsnt may he obtained for five cents ca'ch, by addressing the commlaslannrot Patent- Washington. I). 0." 

